J & J is a privately owned irrigation dam located in Natrona, Wyoming, along the Poison Spider Creek. Built in 1942 by designer Edwin W. Burritt, this earth dam stands 25 feet tall and stretches 918 feet in length. With a storage capacity of 2449 acre-feet and a surface area of 173 acres, the dam serves primarily for irrigation purposes in the region.

Despite its age, J & J has been regulated, inspected, and enforced by the State of Wyoming, ensuring its safe operation and low hazard potential. However, recent condition assessments have deemed its structural integrity as poor, indicating a need for maintenance and potential upgrades. The dam's spillway, an uncontrolled type with a width of 152 feet, poses a moderate risk according to the latest risk assessment.

Located 30 miles from Casper, Wyoming, J & J presents an opportunity for water resource and climate enthusiasts to study the impact of aging infrastructure on water management practices. With its historical significance and operational challenges, this dam serves as a valuable case study for understanding the complexities of maintaining water resources in a changing climate.